What do the terms saturated, unsaturated, and monounsaturated fats mean to your diet and health? These words describe how many hydrogen atoms occur in a molecule, or fundamental unit, of fats and oils, compared with carbon atoms.

A fatty acid molecule is one of the building blocks of fat, and the more hydrogen than carbon that it has, the more saturated it is. Saturated fats are usually solid at room temperature. (Think of bacon grease or a block of cheese.) The less hydrogen than carbon, the more liquid it is. (Think of canola or sunflower seed oil.)

Here are some more fats facts:

Saturated fats (margarine, butter, and coconut oil) are not healthy to use regularly because they contribute to heart disease.

One drawback of polyunsaturated fats, however, is that they spoil more quickly than saturated fats, even when you store them in the refrigerator. Oils high in unsaturated fatty acids (like safflower oil) will go rancid faster when they’re cooked, but can also spoil within several weeks even at room temperature.

Another sneaky process you must watch out for: Manufacturers can heat up unsaturated oils like sunflower seed oil, force hydrogen into it under pressure, and make it more saturated. (You can probably guess that such oils are called hydrogenated or partially hydrogenated.) Margarine is made in this manner to produce a solid that you can spread. These products are not healthy for your heart, and they may increase your risk of developing certain kinds of cancer — not a bargain at any price.